document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=358884>Question 358884</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how can you tell relations is a function on a graph? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #256083 by </B><A HREF=/tutors/aboutme.mpl?userid=neatmath><B>neatmath(302)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=neatmath><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=neatmath><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=256083\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The easiest way to tell if the graph of a relation is a function is to use the vertical line test! <br>\r<BR>\n" );
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document.write( "If you draw a vertical line through any (and all) points on the graph, and the vertical line touches 2 or more points on the graph, then it is NOT a function!<br>\r<BR>\n" );
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document.write( "Remember functions have a 1 to 1 relationship.<br>\r<BR>\n" );
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document.write( "For each x value, there is 1 and only 1 y value.<br>\r<BR>\n" );
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document.write( "So if any x value has 2 or more y values, it can NOT be a function.<br>\r<BR>\n" );
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document.write( "The vertical line test will show this to you graphically.<br>\r<BR>\n" );
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document.write( "If you draw a vertical line through any (and all) points on the graph, and the vertical line touches only 1 point on the graph, then it is a function!<br>\r<BR>\n" );
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document.write( "I hope this helps!<br> </SPAN>\n" );
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